The classical terrestrial network (TN)-based connectivity solution relies on over-engineering and network densification to address the increasing demands; however, such solutions are neither sustainable nor sufficient for the demands of future networks, especially since network densification results in a drain of spatial resources, performance degradation, and significant energy consumption [1]}. Providing a ubiquitous, robust, and balanced wireless service, therefore, requires a paradigm shift in designing future networks [2]}. A recent trend in the wireless communication community is the integration of TN with non-terrestrial networks (NTN) to form a vertical heterogeneous network (VHetNet) [3]}. Along this direction, this article proposes a cloud-enabled high-altitude platform station (HAPS) system architecture that offers joint communication and computation for both aerial and terrestrial users.
The proposed cloud-enabled HAPS provides a high-speed data-sharing fronthaul connection to aerial (hereafter denoted by hot-air balloons) and terrestrial BSs. Furthermore, the proposed system model groups the hot-air balloons and terrestrial BSs into mutually exclusive clusters, where the BSs within a cluster coordinate the resource management and multipoint transmission techniques to provide access to terrestrial and flying users. To this end, the paper focuses on two distinct system performance optimization problems by optimizing the user-to-transmitter scheduling and the corresponding beamforming vectors, which control the level of interference experienced by both flying and ground users in VHetNets.
